diff --git a/lib/src/store/memory.rs b/lib/src/store/memory.rs
index 0665950f..6f671253 100644
--- a/lib/src/store/memory.rs
+++ b/lib/src/store/memory.rs
@@ -266,13 +266,16 @@ impl MemoryStore {
     /// assert_eq!(vec![Quad::new(ex.clone(), ex.clone(), ex.clone(), None)], results);
     /// # oxigraph::Result::Ok(())
     /// ```
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn load_graph(
         &self,
         reader: impl BufRead,
         syntax: GraphSyntax,
         to_graph_name: &GraphName,
         base_iri: Option<&str>,
-    ) -> crate::Result<()> {
+    ) -> Result<(), io::Error> {
         let mut store = self;
         load_graph(&mut store, reader, syntax, to_graph_name, base_iri)
     }
@@ -296,12 +299,15 @@ impl MemoryStore {
     /// assert_eq!(vec![Quad::new(ex.clone(), ex.clone(), ex.clone(), Some(ex.into()))], results);
     /// # oxigraph::Result::Ok(())
     /// ```
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn load_dataset(
         &self,
         reader: impl BufRead,
         syntax: DatasetSyntax,
         base_iri: Option<&str>,
-    ) -> crate::Result<()> {
+    ) -> Result<(), io::Error> {
         let mut store = self;
         load_dataset(&mut store, reader, syntax, base_iri)
     }
@@ -348,6 +354,9 @@ impl MemoryStore {
     /// assert_eq!(file, buffer.as_slice());
     /// # oxigraph::Result::Ok(())
     /// ```
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn dump_graph(
         &self,
         writer: &mut impl Write,
@@ -378,6 +387,9 @@ impl MemoryStore {
     /// assert_eq!(file, buffer.as_slice());
     /// # oxigraph::Result::Ok(())
     /// ```
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn dump_dataset(
         &self,
         writer: &mut impl Write,
@@ -986,7 +998,7 @@ impl<'a> MemoryTransaction<'a> {
         syntax: GraphSyntax,
         to_graph_name: &GraphName,
         base_iri: Option<&str>,
-    ) -> crate::Result<()> {
+    ) -> Result<(), io::Error> {
         load_graph(self, reader, syntax, to_graph_name, base_iri)
     }
 
@@ -1014,7 +1026,7 @@ impl<'a> MemoryTransaction<'a> {
         reader: impl BufRead,
         syntax: DatasetSyntax,
         base_iri: Option<&str>,
-    ) -> crate::Result<()> {
+    ) -> Result<(), io::Error> {
         load_dataset(self, reader, syntax, base_iri)
     }
 
diff --git a/lib/src/store/mod.rs b/lib/src/store/mod.rs
index 8eef6096..c1625217 100644
--- a/lib/src/store/mod.rs
+++ b/lib/src/store/mod.rs
@@ -23,7 +23,7 @@ use rio_api::formatter::{QuadsFormatter, TriplesFormatter};
 use rio_api::parser::{QuadsParser, TriplesParser};
 use rio_turtle::{
     NQuadsFormatter, NQuadsParser, NTriplesFormatter, NTriplesParser, TriGFormatter, TriGParser,
-    TurtleFormatter, TurtleParser,
+    TurtleError, TurtleFormatter, TurtleParser,
 };
 use rio_xml::{RdfXmlError, RdfXmlFormatter, RdfXmlParser};
 use std::collections::HashMap;
@@ -66,45 +66,45 @@ fn load_graph<S: WritableEncodedStore>(
     syntax: GraphSyntax,
     to_graph_name: &GraphName,
     base_iri: Option<&str>,
-) -> Result<(), crate::Error>
-where
-    crate::Error: From<<S as WritableEncodedStore>::Error> + From<<S as StrContainer>::Error>,
-{
+) -> Result<(), io::Error> {
     let base_iri = base_iri.unwrap_or("");
     match syntax {
         GraphSyntax::NTriples => {
-            load_from_triple_parser(store, NTriplesParser::new(reader)?, to_graph_name)
+            load_from_triple_parser(store, NTriplesParser::new(reader), to_graph_name)
         }
         GraphSyntax::Turtle => {
-            load_from_triple_parser(store, TurtleParser::new(reader, base_iri)?, to_graph_name)
+            load_from_triple_parser(store, TurtleParser::new(reader, base_iri), to_graph_name)
         }
         GraphSyntax::RdfXml => {
-            load_from_triple_parser(store, RdfXmlParser::new(reader, base_iri)?, to_graph_name)
+            load_from_triple_parser(store, RdfXmlParser::new(reader, base_iri), to_graph_name)
         }
     }
 }
 
 fn load_from_triple_parser<S: WritableEncodedStore, P: TriplesParser>(
     store: &mut S,
-    mut parser: P,
+    parser: Result<P, P::Error>,
     to_graph_name: &GraphName,
-) -> Result<(), crate::Error>
+) -> Result<(), io::Error>
 where
-    crate::Error: From<P::Error>
-        + From<<S as WritableEncodedStore>::Error>
-        + From<<S as StrContainer>::Error>,
+    IoOrParseError<P::Error>: From<P::Error>,
+    P::Error: Send + Sync + 'static,
 {
+    let mut parser = parser.map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e))?;
     let mut bnode_map = HashMap::default();
     let to_graph_name = store
         .encode_graph_name(to_graph_name)
         .map_err(|e| e.into())?;
-    parser.parse_all(&mut move |t| {
+    let result: Result<(), IoOrParseError<_>> = parser.parse_all(&mut move |t| {
         let quad = store
             .encode_rio_triple_in_graph(t, to_graph_name, &mut bnode_map)
-            .map_err(crate::Error::from)?;
-        store.insert_encoded(&quad).map_err(crate::Error::from)?;
+            .map_err(|e| IoOrParseError::Io(e.into()))?;
+        store
+            .insert_encoded(&quad)
+            .map_err(|e| IoOrParseError::Io(e.into()))?;
         Ok(())
-    })
+    });
+    Ok(result?)
 }
 
 fn dump_graph(
@@ -147,34 +147,34 @@ fn load_dataset<S: WritableEncodedStore>(
     reader: impl BufRead,
     syntax: DatasetSyntax,
     base_iri: Option<&str>,
-) -> Result<(), crate::Error>
-where
-    crate::Error: From<<S as WritableEncodedStore>::Error> + From<<S as StrContainer>::Error>,
-{
+) -> Result<(), io::Error> {
     let base_iri = base_iri.unwrap_or("");
     match syntax {
-        DatasetSyntax::NQuads => load_from_quad_parser(store, NQuadsParser::new(reader)?),
-        DatasetSyntax::TriG => load_from_quad_parser(store, TriGParser::new(reader, base_iri)?),
+        DatasetSyntax::NQuads => load_from_quad_parser(store, NQuadsParser::new(reader)),
+        DatasetSyntax::TriG => load_from_quad_parser(store, TriGParser::new(reader, base_iri)),
     }
 }
 
 fn load_from_quad_parser<S: WritableEncodedStore, P: QuadsParser>(
     store: &mut S,
-    mut parser: P,
-) -> Result<(), crate::Error>
+    parser: Result<P, P::Error>,
+) -> Result<(), io::Error>
 where
-    crate::Error: From<P::Error>
-        + From<<S as WritableEncodedStore>::Error>
-        + From<<S as StrContainer>::Error>,
+    IoOrParseError<P::Error>: From<P::Error>,
+    P::Error: Send + Sync + 'static,
 {
+    let mut parser = parser.map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e))?;
     let mut bnode_map = HashMap::default();
-    parser.parse_all(&mut move |q| {
+    let result: Result<(), IoOrParseError<_>> = parser.parse_all(&mut move |q| {
         let quad = store
             .encode_rio_quad(q, &mut bnode_map)
-            .map_err(crate::Error::from)?;
-        store.insert_encoded(&quad).map_err(crate::Error::from)?;
+            .map_err(|e| IoOrParseError::Io(e.into()))?;
+        store
+            .insert_encoded(&quad)
+            .map_err(|e| IoOrParseError::Io(e.into()))?;
         Ok(())
-    })
+    });
+    Ok(result?)
 }
 
 fn dump_dataset(
@@ -200,3 +200,35 @@ fn dump_dataset(
     }
     Ok(())
 }
+
+enum IoOrParseError<E: Sized> {
+    Io(io::Error),
+    Parse(E),
+}
+
+impl<E: Sized> From<io::Error> for IoOrParseError<E> {
+    fn from(error: io::Error) -> Self {
+        Self::Io(error)
+    }
+}
+
+impl From<TurtleError> for IoOrParseError<TurtleError> {
+    fn from(error: TurtleError) -> Self {
+        Self::Parse(error)
+    }
+}
+
+impl From<RdfXmlError> for IoOrParseError<RdfXmlError> {
+    fn from(error: RdfXmlError) -> Self {
+        Self::Parse(error)
+    }
+}
+
+impl<E: Sized + Error + Send + Sync + 'static> From<IoOrParseError<E>> for io::Error {
+    fn from(error: IoOrParseError<E>) -> Self {
+        match error {
+            IoOrParseError::Io(error) => error,
+            IoOrParseError::Parse(error) => io::Error::new(io::ErrorKind::InvalidData, error),
+        }
+    }
+}
diff --git a/lib/src/store/rocksdb.rs b/lib/src/store/rocksdb.rs
index 7952f86e..2b09541b 100644
--- a/lib/src/store/rocksdb.rs
+++ b/lib/src/store/rocksdb.rs
@@ -184,6 +184,10 @@ impl RocksDbStore {
     /// only a part of it may be written. Use a (memory greedy) transaction if you do not want that.
     ///
     /// See `MemoryStore` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
+    /// Errors related to data loading into the store use the other error kinds.
     pub fn load_graph(
         &self,
         reader: impl BufRead,
@@ -202,6 +206,10 @@ impl RocksDbStore {
     /// only a part of it may be written. Use a (memory greedy) transaction if you do not want that.
     ///
     /// See `MemoryStore` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
+    /// Errors related to data loading into the store use the other error kinds.
     pub fn load_dataset(
         &self,
         reader: impl BufRead,
@@ -567,13 +575,16 @@ impl RocksDbTransaction<'_> {
     /// Do not use for big files.
     ///
     /// See `MemoryTransaction` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn load_graph(
         &mut self,
         reader: impl BufRead,
         syntax: GraphSyntax,
         to_graph_name: &GraphName,
         base_iri: Option<&str>,
-    ) -> Result<(), crate::Error> {
+    ) -> Result<(), io::Error> {
         load_graph(&mut self.inner, reader, syntax, to_graph_name, base_iri)
     }
 
@@ -584,12 +595,15 @@ impl RocksDbTransaction<'_> {
     /// Do not use for big files.
     ///
     /// See `MemoryTransaction` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn load_dataset(
         &mut self,
         reader: impl BufRead,
         syntax: DatasetSyntax,
         base_iri: Option<&str>,
-    ) -> Result<(), crate::Error> {
+    ) -> Result<(), io::Error> {
         load_dataset(&mut self.inner, reader, syntax, base_iri)
     }
 
diff --git a/lib/src/store/sled.rs b/lib/src/store/sled.rs
index dd45a3df..0ad80c0e 100644
--- a/lib/src/store/sled.rs
+++ b/lib/src/store/sled.rs
@@ -169,13 +169,17 @@ impl SledStore {
     /// only a part of it may be written. Use a (memory greedy) transaction if you do not want that.
     ///
     /// See `MemoryStore` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
+    /// Errors related to data loading into the store use the other error kinds.
     pub fn load_graph(
         &self,
         reader: impl BufRead,
         syntax: GraphSyntax,
         to_graph_name: &GraphName,
         base_iri: Option<&str>,
-    ) -> Result<(), crate::Error> {
+    ) -> Result<(), io::Error> {
         load_graph(
             &mut DirectWriter::new(self),
             reader,
@@ -191,12 +195,16 @@ impl SledStore {
     /// only a part of it may be written. Use a (memory greedy) transaction if you do not want that.
     ///
     /// See `MemoryStore` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
+    /// Errors related to data loading into the store use the other error kinds.
     pub fn load_dataset(
         &self,
         reader: impl BufRead,
         syntax: DatasetSyntax,
         base_iri: Option<&str>,
-    ) -> Result<(), crate::Error> {
+    ) -> Result<(), io::Error> {
         load_dataset(&mut DirectWriter::new(self), reader, syntax, base_iri)
     }
 
@@ -658,13 +666,16 @@ impl SledTransaction<'_> {
     /// Do not use for big files.
     ///
     /// See `MemoryTransaction` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn load_graph(
         &mut self,
         reader: impl BufRead,
         syntax: GraphSyntax,
         to_graph_name: &GraphName,
         base_iri: Option<&str>,
-    ) -> Result<(), crate::Error> {
+    ) -> Result<(), io::Error> {
         load_graph(&mut self.inner, reader, syntax, to_graph_name, base_iri)
     }
 
@@ -675,12 +686,15 @@ impl SledTransaction<'_> {
     /// Do not use for big files.
     ///
     /// See `MemoryTransaction` for a usage example.
+    ///
+    /// Errors related to parameter validation like the base IRI use the `INVALID_INPUT` error kind.
+    /// Errors related to a bad syntax in the loaded file use the `INVALID_DATA` error kind.
     pub fn load_dataset(
         &mut self,
         reader: impl BufRead,
         syntax: DatasetSyntax,
         base_iri: Option<&str>,
-    ) -> Result<(), crate::Error> {
+    ) -> Result<(), io::Error> {
         load_dataset(&mut self.inner, reader, syntax, base_iri)
     }
 
diff --git a/python/src/memory_store.rs b/python/src/memory_store.rs
index 9f097e50..cae216b1 100644
--- a/python/src/memory_store.rs
+++ b/python/src/memory_store.rs
@@ -58,7 +58,7 @@ impl PyMemoryStore {
         let results = self
             .inner
             .query(query, QueryOptions::default())
-            .map_err(|e| ParseError::py_err(e.to_string()))?;
+            .map_err(|e| ValueError::py_err(e.to_string()))?;
         query_results_to_python(py, results)
     }
 
@@ -89,7 +89,7 @@ impl PyMemoryStore {
                     &to_graph_name.unwrap_or(GraphName::DefaultGraph),
                     base_iri,
                 )
-                .map_err(|e| ParseError::py_err(e.to_string()))
+                .map_err(map_io_err)
         } else if let Some(dataset_syntax) = DatasetSyntax::from_media_type(mime_type) {
             if to_graph_name.is_some() {
                 return Err(ValueError::py_err(
@@ -98,7 +98,7 @@ impl PyMemoryStore {
             }
             self.inner
                 .load_dataset(Cursor::new(data), dataset_syntax, base_iri)
-                .map_err(|e| ParseError::py_err(e.to_string()))
+                .map_err(map_io_err)
         } else {
             Err(ValueError::py_err(format!(
                 "Not supported MIME type: {}",
diff --git a/python/src/sled_store.rs b/python/src/sled_store.rs
index b3b2c2ee..a4061b44 100644
--- a/python/src/sled_store.rs
+++ b/python/src/sled_store.rs
@@ -3,7 +3,7 @@ use crate::store_utils::*;
 use oxigraph::model::*;
 use oxigraph::sparql::QueryOptions;
 use oxigraph::{DatasetSyntax, GraphSyntax, SledStore};
-use pyo3::exceptions::{IOError, ValueError};
+use pyo3::exceptions::ValueError;
 use pyo3::prelude::*;
 use pyo3::types::PyTuple;
 use pyo3::{PyIterProtocol, PyObjectProtocol, PySequenceProtocol};
@@ -22,23 +22,19 @@ impl PySledStore {
     fn new(path: Option<&str>) -> PyResult<Self> {
         Ok(Self {
             inner: if let Some(path) = path {
-                SledStore::open(path).map_err(|e| IOError::py_err(e.to_string()))?
+                SledStore::open(path).map_err(map_io_err)?
             } else {
-                SledStore::new().map_err(|e| IOError::py_err(e.to_string()))?
+                SledStore::new().map_err(map_io_err)?
             },
         })
     }
 
     fn add(&self, quad: &PyTuple) -> PyResult<()> {
-        self.inner
-            .insert(&extract_quad(quad)?)
-            .map_err(|e| IOError::py_err(e.to_string()))
+        self.inner.insert(&extract_quad(quad)?).map_err(map_io_err)
     }
 
     fn remove(&self, quad: &PyTuple) -> PyResult<()> {
-        self.inner
-            .remove(&extract_quad(quad)?)
-            .map_err(|e| IOError::py_err(e.to_string()))
+        self.inner.remove(&extract_quad(quad)?).map_err(map_io_err)
     }
 
     fn r#match(
@@ -64,7 +60,7 @@ impl PySledStore {
         let results = self
             .inner
             .query(query, QueryOptions::default())
-            .map_err(|e| ParseError::py_err(e.to_string()))?;
+            .map_err(|e| ValueError::py_err(e.to_string()))?;
         query_results_to_python(py, results)
     }
 
@@ -95,7 +91,7 @@ impl PySledStore {
                     &to_graph_name.unwrap_or(GraphName::DefaultGraph),
                     base_iri,
                 )
-                .map_err(|e| ParseError::py_err(e.to_string()))
+                .map_err(map_io_err)
         } else if let Some(dataset_syntax) = DatasetSyntax::from_media_type(mime_type) {
             if to_graph_name.is_some() {
                 return Err(ValueError::py_err(
@@ -104,7 +100,7 @@ impl PySledStore {
             }
             self.inner
                 .load_dataset(Cursor::new(data), dataset_syntax, base_iri)
-                .map_err(|e| ParseError::py_err(e.to_string()))
+                .map_err(map_io_err)
         } else {
             Err(ValueError::py_err(format!(
                 "Not supported MIME type: {}",
@@ -134,7 +130,7 @@ impl PySequenceProtocol for PySledStore {
     fn __contains__(&self, quad: &PyTuple) -> PyResult<bool> {
         self.inner
             .contains(&extract_quad(quad)?)
-            .map_err(|e| IOError::py_err(e.to_string()))
+            .map_err(map_io_err)
     }
 }
 
@@ -163,12 +159,7 @@ impl PyIterProtocol for QuadIter {
     ) -> PyResult<Option<(PyObject, PyObject, PyObject, PyObject)>> {
         slf.inner
             .next()
-            .map(move |q| {
-                Ok(quad_to_python(
-                    slf.py(),
-                    q.map_err(|e| IOError::py_err(e.to_string()))?,
-                ))
-            })
+            .map(move |q| Ok(quad_to_python(slf.py(), q.map_err(map_io_err)?)))
             .transpose()
     }
 }
diff --git a/python/src/store_utils.rs b/python/src/store_utils.rs
index f93ebb88..9f896950 100644
--- a/python/src/store_utils.rs
+++ b/python/src/store_utils.rs
@@ -2,12 +2,11 @@ use crate::model::*;
 use oxigraph::model::*;
 use oxigraph::sparql::{QueryResult, QuerySolution, QuerySolutionsIterator};
 use oxigraph::Result;
-use pyo3::exceptions::{IOError, TypeError};
+use pyo3::exceptions::{IOError, TypeError, ValueError};
 use pyo3::prelude::*;
-use pyo3::{create_exception, PyIterProtocol, PyMappingProtocol, PyNativeType, PyObjectProtocol};
+use pyo3::{PyIterProtocol, PyMappingProtocol, PyNativeType, PyObjectProtocol};
 use std::fmt::Write;
-
-create_exception!(oxigraph, ParseError, pyo3::exceptions::Exception);
+use std::io;
 
 pub fn extract_quads_pattern(
     subject: &PyAny,
@@ -140,3 +139,12 @@ impl PyIterProtocol for TripleResultIter {
             .map(move |t| triple_to_python(slf.py(), t)))
     }
 }
+
+pub fn map_io_err(error: io::Error) -> PyErr {
+    match error.kind() {
+        io::ErrorKind::InvalidInput | io::ErrorKind::InvalidData => {
+            ValueError::py_err(error.to_string())
+        }
+        _ => IOError::py_err(error.to_string()),
+    }
+}