diff --git a/assemblyai/__version__.py b/assemblyai/__version__.py
index e0d0ed6..98bb08f 100644
--- a/assemblyai/__version__.py
+++ b/assemblyai/__version__.py
@@ -1 +1 @@
-__version__ = "0.35.0"
+__version__ = "0.35.1"
diff --git a/assemblyai/types.py b/assemblyai/types.py
index 1c6f3de..412d248 100644
--- a/assemblyai/types.py
+++ b/assemblyai/types.py
@@ -9,12 +9,15 @@
 
 try:
     # pydantic v2 import
-    from pydantic import UUID4, BaseModel, Field
+    from pydantic import UUID4, BaseModel, ConfigDict, Field
     from pydantic_settings import BaseSettings, SettingsConfigDict
+
+    pydantic_v2 = True
 except ImportError:
     # pydantic v1 import
-    from pydantic.v1 import UUID4, BaseModel, BaseSettings, Field
-    from pydantic.v1 import ConfigDict as SettingsConfigDict
+    from pydantic.v1 import UUID4, BaseModel, BaseSettings, ConfigDict, Field
+
+    pydantic_v2 = False
 
 from typing_extensions import Self
 
@@ -80,9 +83,15 @@ class Settings(BaseSettings):
     base_url: str = "https://api.assemblyai.com"
     "The base URL for the AssemblyAI API"
 
-    polling_interval: float = Field(default=3.0, gte=0.1)
+    polling_interval: float = Field(default=3.0, gt=0.0)
     "The default polling interval for long-running requests (e.g. polling the `Transcript`'s status)"
-    model_config = SettingsConfigDict(env_prefix="assemblyai_")
+
+    if pydantic_v2:
+        model_config = SettingsConfigDict(env_prefix="assemblyai_")
+    else:
+
+        class Config:
+            env_prefix = "assemblyai_"
 
 
 class TranscriptStatus(str, Enum):
@@ -571,7 +580,7 @@ class RawTranscriptionConfig(BaseModel):
     """
     The speech model to use for the transcription.
     """
-    model_config = SettingsConfigDict(extra="allow")
+    model_config = ConfigDict(extra="allow")
 
 
 class TranscriptionConfig:
@@ -1796,7 +1805,7 @@ class ListTranscriptParameters(BaseModel):
 
     throttled_only: Optional[bool] = None
     "Get only throttled transcripts, overrides the status filter"
-    model_config = SettingsConfigDict(use_enum_values=True)
+    model_config = ConfigDict(use_enum_values=True)
 
 
 class PageDetails(BaseModel):
diff --git a/tests/unit/test_settings.py b/tests/unit/test_settings.py
new file mode 100644
index 0000000..25b6df4
--- /dev/null
+++ b/tests/unit/test_settings.py
@@ -0,0 +1,75 @@
+import os
+from importlib import reload
+
+import assemblyai as aai
+
+
+def test_api_key_settings():
+    """
+    Tests that `ASSEMBLYAI_API_KEY` works correctly
+    """
+    tmp1 = os.environ.pop("ASSEMBLYAI_API_KEY", None)
+    tmp2 = os.environ.pop("API_KEY", None)
+
+    aai.settings.api_key = None
+    reload(aai)
+    assert aai.settings.api_key is None
+
+    # this should not change the api key
+    os.environ["API_KEY"] = "test"
+    reload(aai)
+    assert aai.settings.api_key is None
+
+    # this should change the api key
+    os.environ["ASSEMBLYAI_API_KEY"] = "test"
+    reload(aai)
+    assert aai.settings.api_key == "test"
+
+    # reset
+    if tmp1:
+        os.environ["ASSEMBLYAI_API_KEY"] = tmp1
+    else:
+        os.environ.pop("ASSEMBLYAI_API_KEY", None)
+
+    if tmp2:
+        os.environ["API_KEY"] = tmp2
+    else:
+        os.environ.pop("API_KEY", None)
+
+    reload(aai)
+    aai.settings.api_key = "test"
+
+
+def test_base_url_settings():
+    """
+    Tests that `ASSEMBLY_BASE_URL` works correctly
+    """
+    tmp1 = os.environ.pop("ASSEMBLYAI_BASE_URL", None)
+    tmp2 = os.environ.pop("BASE_URL", None)
+
+    aai.settings.base_url = "https://api.assemblyai.com"
+    reload(aai)
+    assert aai.settings.base_url == "https://api.assemblyai.com"
+
+    # this should not change the base url
+    os.environ["BASE_URL"] = "https://test.com"
+    reload(aai)
+    assert aai.settings.base_url == "https://api.assemblyai.com"
+
+    # this should change the base url
+    os.environ["ASSEMBLYAI_BASE_URL"] = "https://test.com"
+    reload(aai)
+    assert aai.settings.base_url == "https://test.com"
+
+    # reset
+    if tmp1:
+        os.environ["ASSEMBLYAI_BASE_URL"] = tmp1
+    else:
+        os.environ.pop("ASSEMBLYAI_BASE_URL", None)
+    if tmp2:
+        os.environ["BASE_URL"] = tmp2
+    else:
+        os.environ.pop("BASE_URL", None)
+
+    reload(aai)
+    aai.settings.api_key = "test"